BirdAnalyst
Species · BCR 13 · BBS 2025 Release · 1966–2024

Ruffed Grouse In Lower Great Lakes / St. Lawrence Plain

All regionsLower Great Lakes / St. Lawrence PlainGeneralists

Ruffed Grouse in Lower Great Lakes / St. Lawrence Plain has fallen sharply: down 56% on the route-weighted index since 1969.

-56%Since 1969TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
43Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
45YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Ruffed Grouse has fallen sharply in Lower Great Lakes / St. Lawrence Plain: down 56% on the route-weighted index since 1969.

Forecast

If the recent trend holds, Ruffed Grouse in Lower Great Lakes / St. Lawrence Plain is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±43.3%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
0.01Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0995% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±43.3%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Ruffed Grouse in Lower Great Lakes / St. Lawrence Plain is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±43.3%, with 100% of held-out values landing inside the 95% band.19672029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20250.010.000.09
20260.010.000.09
20270.010.000.09
20280.010.000.09
20290.010.000.09

Routes In Lower Great Lakes / St. Lawrence Plain

Routes recording Ruffed Grouse in Lower Great Lakes / St. Lawrence Plain.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
HarmonsburgPENNSYLVANIA61977
TrumansburgNEW-YORK21988
OneidaNEW-YORK22010
RhinebeckNEW-YORK11979
HighlandNEW-YORK11995
W ShokanNEW-YORK11984
AusterlitzNEW-YORK12005
CatskillsNEW-YORK11973
DuanesburgNEW-YORK11976
Oriskany FlsNEW-YORK12024
CayugaNEW-YORK11976
BranchportNEW-YORK12001
Canadice LNEW-YORK11971
Mt MorrisNEW-YORK12007
West SenecaNEW-YORK11988
CastileNEW-YORK12003
RandolphNEW-YORK11987
SheridanNEW-YORK11993
Cherry HillNEW-YORK11987
NashvilleNEW-YORK11994
WatertownNEW-YORK12004
Alder CreekNEW-YORK11988
N WilmurtNEW-YORK11991
SalemNEW-YORK11990
ArgyleNEW-YORK11996

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.